Pro-immigration activists gather in front of the U.S. Supreme Court on April 18, 2016, in Washington.

Photographer: Alex Wong/Getty Images

U.S. Supreme Court justices suggested they are divided on a challenge to President Barack Obama’s plan to shield millions of unauthorized immigrants from deportation.

Hearing arguments in a case that will shape Obama’s legacy and the November election, the justices clashed Monday over contentions that the president overstepped his authority when he announced the executive action in 2014.

The 90-minute session suggested the court might divide 4-4 -- an outcome that would leave intact a lower court ruling blocking the plan. Some justices, however, discussed an approach that would uphold most of the policy -- letting Obama shield people from deportation and make them eligible to seek work permits, while potentially opening questions about whether they would be eligible for Social Security benefits.

The likely swing votes in the case -- Chief Justice John Roberts and Justice Anthony Kennedy -- both aimed skeptical questions at the Obama administration lawyer defending the plan.

"It’s as if the president is setting a policy and the Congress is executing it,” Kennedy told U.S. Solicitor General Donald Verrilli. “That’s just upside down.”

Justice Ruth Bader Ginsburg countered that with 11 million undocumented immigrants in the U.S., “inevitably priorities have to be set" about how to handle them.

Justice Sonia Sotomayor said those 11 million "are here in the shadows" and affecting the economy. She said Congress hadn’t appropriated the money to deport more than a small fraction of that group.

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Texas and 25 other mostly Republican-led states are suing over the policy, saying that federal immigration statutes laws don’t let the president shield such a large category of people from deportation or let them seek work permits. The president says the program is simply a broader exercise of his accepted power to set priorities in deciding who should be deported. The administration is trying to overturn a federal appeals court ruling that blocked the plan.

Political Fireworks

The case is fraught with political implications. Immigration is already a hot topic in the presidential campaign, with leading Republican candidates Donald Trump and Ted Cruz saying they would deport the 11 million people who are in the country illegally. Even if the Supreme Court upholds Obama’s policy, a victory by Trump or Cruz in November would mean the new president could rescind the plan.

The Feb. 13 death of Justice Antonin Scalia has complicated the case, raising the prospect of a 4-4 split that would leave intact the lower court decision and a trial judge’s order blocking the policy from taking effect.

Under Obama’s plan, known as DAPA, people whose children are either U.S. citizens or legal permanent residents, and who meet other requirements, could get relief from deportation for three years plus the right to apply for work permits. Those people, who are primarily from Mexico and Central America, wouldn’t be given an easier path to citizenship.

The administration says about 4 million people would qualify for DAPA, although estimates vary.

Legal Status

Roberts may hold the key to the case. He repeatedly voiced doubt about Verrilli’s procedural argument that the states lack the legal right to challenge the plan.

The chief justice also questioned Verrilli’s contention that people who receive deferred deportation wouldn’t be granted any legal status. Roberts pointed to a line in the policy that said those people would be deemed "lawfully present" in the country.

"Lawfully present does not mean you’re legally present in the United States?" Roberts asked.

Verrilli characterized the phrase "lawfully present" as a term that alluded to rights people would have under other regulations -- including the right to Social Security benefits -- without having any legal effect. Verrilli said the court could "put a red pencil" through that sentence without changing the meaning of the policy.

Although Roberts didn’t indicate he was satisfied, he later asked Erin Murphy, a lawyer arguing against the plan on behalf of the House of Representatives, whether that was a viable solution.

Solicitor General

Murphy and Texas Solicitor General Scott Keller said that striking the sentence wouldn’t fix the problem.

"The reason is because what the executive is doing when they’re granting deferred action is they are affirmatively granting a status," Keller said.

Two members of the court’s liberal wing -- Justices Elena Kagan and Stephen Breyer -- also asked about the implications of eliminating the "lawfully present" characterization from the policy.

Kagan asked Keller whether the Department of Homeland Security could issue deferred deportation to a much smaller group of people, such as those who had been in the country for 25 years. After some back and forth, Keller eventually said no.

"So this has nothing to do with the scope of this policy," Kagan said.

Many Observers

The justices heard arguments before a packed courtroom that included a number of unauthorized immigrants. Those included Juergen Nino, 32, who drove 30 hours from his home in Abilene, Texas, to see a case that might determine whether he can remain with his 2-year-old daughter.

"I want to be able to see her growing up next to me," said Nino, a native Nicaraguan.

The Senate’s second-ranking Democrat, Dick Durbin of Illinois, also attended the argument and told reporters afterward the case could end up in a 4-4 decision that leaves millions of people in limbo.

"This vacancy on the Supreme Court could make the difference,” Durbin said. “The Republicans in the Senate who are refusing to fill the Scalia vacancy could have an impact causing confusion across the United States just because of cases as important as this."

When it agreed to take up the case in January, the court opened the possibility of a broader ruling curbing the president’s constitutional powers. The justices said they would consider Texas’s argument that Obama violated his constitutional duty to "take care that the laws be faithfully executed." That issue, however, didn’t arise during Monday’s session.